As agnostic-towards-atheist parents, my husband and I often find ourselves defaulting to "Some people believe x, some people believe y, and we aren't really sure god exists at all." The wee ones are now going on 7 and 8 and the psychological damage doesn't seem too severe. Yet.
Don't worry. Jack will still think you're the bee's knees no matter what. And just wait til you see some of those traits you don't love about yourself staring you right back in the face. Good times.